code: def test_function_signature(self):
      def foo(image, label=None, *a, **kw):
          pass
  
      _ = FunctionSignature(foo)
  
file_path: MONAI/tests/test_adaptors.py
imports: from __future__ import annotations
  import itertools
  import unittest
  from monai.transforms.adaptors import FunctionSignature, adaptor, apply_alias, to_kwargs
label_desc: Use image node_id 1 for calling the TestAdaptors obj's underlying member method code with example usage: obj.test_function_signature() without return types